The present invention relates to compounds able to inhibit calciumreceptor activity and the use of such compounds. Preferably, the compounds described herein are administered to patients to achieve a therapeutic effect.
Certain cells in the body respond not only to chemical signals, but also to ions such as extracellular calcium ions (Ca2+). Extracellular Ca2+ is under tight homeostatic control and regulates various processes such as blood clotting, nerve and muscle excitability, and proper bone formation.
Calcium receptor proteins enable certain specialized cells to respond to changes in extracellular Ca2+ concentration. For example, extracellular Ca2+ inhibits the secretion of parathyroid hormone (PTH) from parathyroid cells, inhibits bone resorption by osteoclasts, and stimulates secretion of calcitonin from C-cells.
PTH is the principal endocrine factor regulating Ca2+ homeostasis in the blood and extracellular fluids. PTH, by acting on bone and kidney cells, increases the level of Ca2+ in the blood. This increase in extracellular Ca2+ then acts as a negative feedback signal, depressing PTH secretion. The reciprocal relationship between extracellular Ca2+ and PTH secretion forms an important mechanism maintaining bodily Ca2+ homeostasis.
Extracellular Ca2+ acts directly on parathyroid cells to regulate PTH secretion. The existence of a parathyroid cell surface protein which detects changes in extracellular Ca2+ has been confirmed. (Brown et al., Nature 366:574, 1993.) In parathyroid cells, this protein, the calcium receptor, acts as a receptor for extracellular Ca2+, detects changes in the ion concentration of extracellular Ca2+, and initiates a functional cellular response, PTH secretion.
Extracellular Ca2+ can exert effects on different cell functions, reviewed in Nemeth et al., Cell Calcium 11:319, 1990. The role of extracellular Ca2+ in parafollicular (C-cells) and parathyroid cells is discussed in Nemeth, Cell Calcium 11:323, 1990. These cells were shown to express similar calcium receptors. (See, Brown et al., Nature 366:574, 1993; Mithal et al., J. Bone Miner. Res. 9, Suppl. 1, s282, 1994; Rogers et al., J. Bone Miner. Res. 9, Suppl, 1, s409, 1994; Garrett et al., Endocrinology 136:5202-5211, 1995.) The role of extracellular Ca2+ on bone osteoclasts is discussed by Zaidi, Bioscience Reports 10:493, 1990.
The ability of various molecules to mimic extracellular Ca2+ in vitro is discussed in references such as Nemeth et al., in xe2x80x9cCalcium-Binding Proteins in Health and Disease,xe2x80x9d 1987, Academic Press, Inc., pp. 33-35; Brown et al., Endocrinology 128:3047, 1991; Chen et al., J. Bone Miner. Res. 5:581, 1990; and Zaidi et al., Biochem. Biophys. Res. Commun. 167:807, 1990.
Nemeth et al., PCT/US92/07175, International Publication number WO 93/04373, Nemeth et al., PCT/US93/01642, international Publication Number WO 94/18959, and Nemeth et al., PCT/US94/12117, International Publication Number WO 95/11211, feature calcium receptor-active molecules and refer to calcilytics as compounds able to inhibit calcium receptor activity. For example, WO 94/18959 on page 8, lines 2-13 asserts:
Applicant is also the first to describe methods by which molecules active at these Ca2+ receptors can be identified and used as lead molecules in the discovery, development, design, modification and/or construction of useful calcimimetics or calcilytics which are active at Ca2+ receptors. Such calcimimetics or calcilytics are useful in the treatment of various disease states characterized by abnormal levels of one or more components, e.g., polypeptides such as hormones, enzymes or growth factors, the expresssion and/or secretion of which is regulated or affected by activity at one or more Ca2+ receptors.
The references provided in the background are not admitted to be prior art to the pending claims.
The present invention features calcilytic compounds. xe2x80x9cCalcilytic compoundsxe2x80x9d refer to compounds able to inhibit calcium receptor activity. The ability of a compound to xe2x80x9cinhibit calcium receptor activityxe2x80x9d means that the compound causes a decrease in one or more calcium receptor activities evoked by extracellular Ca2+.
The use of calcilytic compounds to inhibit calcium receptor activity and/or achieve a beneficial effect in a patient are described below. Also described below are techniques which can be used to obtain additional calcilytic compounds.
An example of featured calcilytic compounds are Structure I xcex1,xcex1-disubstituted arylalkylamine derivatives having the chemical formula: 
where R1 is selected from the group consisting of: aryl, longer-length alk, and cycloalk;
R2 is selected from the group consisting of: lower alk, cycloalk, alkoxy, H, OH, xe2x95x90O, C(O)OH, C(O)O-lower alk, C(O)NH-lower alk, C(O)N(lower alk)2, SH, S-lower alk, NH2, NH-lower alk, and N(lower alk)2;
R3 and R4 is each independently lower alk or together cyclopropyl;
R5 is aryl;
R6 if present is either hydrogen, lower alkyl or lower alkenyl, wherein R6 is not.present if R2 is xe2x95x90O;
Y1 is either covalent bond, alkylene, or alkenylene; is Y2 is alkylene;
Y3 is alkylene; and
Z is selected from the group consisting of: covalent bond, O, S, NH, N-lower alk, alkylene, alkenylene, and alkynylene, provided that if Z is either O, S, NH, or N-lower alk, then Y1 is not a covalent bond, further provided that Y1 and Z may together be a covalent bond;
and pharmaceutically acceptable salts and complexes thereof.
The terms aryl, longer-length alk, lower alk, cycloalk, alkoxy, alkylene, alkenylene, and alkynylene, along with possible substituents are defined in Section II, infra. Section II, infra, also provides definitions for other chemical groups described in the present application.
Preferred calcilytic compounds have an IC50xe2x89xa650 xcexcM, more preferably an IC50xe2x89xa610 xcexcM, and even more preferably an IC50xe2x89xa61 xcexcM, as measured using the xe2x80x9cCalcium Receptor Inhibitor Assayxe2x80x9d described in Example 1, infra.
Thus, a first aspect of the present invention features a method of treating a patient by administering to the patient a therapeutically effective amount of a Structure I xcex1,xcex1-disubstituted arylalkylamine derivative. Treatment can be carried out, for example, to retard the disease in a patient having a disease or to prophylactically retard or prevent the onset of a disease.
A therapeutically effective amount is the amount of compound which achieves a therapeutic effect by retarding a disease in a patient having a disease or prophylactically retarding or preventing the onset of a disease. Preferably, it is an amount which relieves to some extent one or more symptoms of a disease or disorder in a patient; returns to normal either partially or completely one or more physiological or biochemical parameters associated with or causative of the disease or disorder; and/or reduces the likelihood of the onset of the disease of disorder.
A xe2x80x9cpatientxe2x80x9d refers to a mammal in which compounds characterized by their ability to inhibit calcium receptor activity, in vivo or in vitro, will have a beneficial effect. Preferably, the patient is a human being.
Patients benefiting from the administration of a therapeutic amount of a calcilytic compound can be identified using standard techniques known to those in the medical profession. Diseases or disorders which can be treated by inhibiting one or more calcium receptor activities include one or more of the following types: (1) those characterized by an abnormal bone and mineral homeostasis; (2) those characterized by an abnormal amount of an extracellular or intracellular messenger whose production can be affected by one or more calcium receptor activities; (3) those characterized by an abnormal effect (e.g., a different effect in kind or magnitude) of an intracellular or extracellular messenger which can itself be ameliorated by one or more calcium receptor activities; and (4) other diseases or disorders where inhibition of one or more calcium receptor activities exerts a beneficial effect, for example, in diseases or disorders where the production of an intracellular or extracellular messenger stimulated by receptor activity compensates for an abnormal amount of a different messenger. Examples of extracellular messengers whose secretion and/or effect can be affected by inhibiting calcium receptor activity are believed to include inorganic ions, hormones, neurotransmitters, growth factors, and chemokines. Examples of intracellular messengers include cAMP, cGMP, IP3, calcium, magnesium, and diacylglycerol.
Preferably, a patient is a human having a disease or disorder characterized by one or more of the following: (1) an abnormal bone or mineral homeostasis; (2) an abnormal amount of an extracellular or intracellular messenger which is ameliorated by a compound able to effect one or more calcium receptor activities; and (3) an abnormal effect of an intracellular or extracellular messenger which is ameliorated by a compound able to effect one or more calcium receptor activities.
Preferably, the disease or disorder is characterized by an abnormal bone and mineral homeostasis, more preferably calcium homeostasis. Abnormal calcium homeostasis is characterized by one or more of the following activities: (1) an abnormal increase or decrease in serum calcium; (2) an abnormal increase or decrease in urinary excretion of calcium; (3) an abnormal increase or decrease in bone calcium levels, for example, as assessed by bone mineral density measurements; (4) an abnormal absorption of dietary calcium; (5) an abnormal increase or decrease in the production and/or release of messengers which affect serum calcium levels such as PTH and calcitonin; and (6) an abnormal change in the response elicited by messengers which affect serum calcium levels. The abnormal increase or decrease in these different aspects of calcium homeostasis is relative to that occurring in the general population and is generally associated with a disease or disorder.
Preferably, the calcilytic compounds are used to treat diseases or disorders selected from the group consisting of: hypoparathyroidism, osteosarcoma, periodontal disease, fracture healing, osteoarthritis, rheumatoid arthritis, Paget""s disease, humoral hypercalcemia malignancy, and osteoporosis.
Another aspect of the present invention describes a method of treating a patient comprising the step of administering to the patient an amount of a calcilytic compound sufficient to increase serum PTH level. Preferably, the method is carried out by administering an amount of the compound effective to cause an increase in duration and/or quantity of serum PTH level sufficient to have a therapeutic effect.
Increasing serum PTH may be used to achieve a therapeutic effect by retarding a disease in a patient having the disease or prophylactically retarding or preventing the onset of a disease. Prophylactic treatment can be performed, for example, on a person with an abnormally low serum PTH; or on a person without a low serum PTH, but were increasing PTH has a beneficial effect. An abnormally low serum PTH is a serum PTH level lower than that occurring in the general population, and is preferably an amount associated with a disease or the onset of a disease.
Increasing serum PTH levels can be used to treat different types of diseases including bone and mineral related diseases.
In different embodiments, the compound administered to a patient causes an increase in serum PTH having a duration up to one hour, about one to about twenty-four hours, about one to about twelve hours, about one to about six hours, about one to about five hours, about one to about four hours, about two to about five hours, about two to about four hours, or about three to about six hours.
In additional different embodiments, the compound administered to a patient causes an increase in serum PTH up to 0.5 fold, 0.5 to 5 fold, 5 fold to 10 ten fold, and at least 10 fold, greater than peak serum PTH in the patient. The peak serum level is measured with respect to the patient not undergoing treatment.
Another aspect of the present invention features Structure I calcilytic compounds.
Another aspect of the present invention features a pharmaceutical composition comprising a pharmaceutically acceptable carrier and a calcilytic compound described herein. The pharmaceutical composition contains the calcilytic compound in a form suitable for administration into a mammal, preferably, a human being. Preferably, the pharmaceutical composition contains an amount of a calcilytic compound in a proper pharmaceutical dosage form sufficient to exert a therapeutic effect on a human being. However, multiple doses of pharmaceutical compositions may be used to treat a patient.
Considerations and factors concerning dosage forms suitable for administration are known in the art and include potential toxic effects, solubility, route of administration, and maintaining activity. For example, pharmaceutical compositions injected into the bloodstream should be soluble.
Another aspect of the present invention features a method of screening for Structure I xcex1,xcex1-disubstituted arylalkylamine derivatives able to inhibit calcium receptor activity. The method involves the steps of contacting a cell having a calcium receptor with a Structure I xcex1,xcex1-di-substituted arylalkylamine derivative and measuring the ability of the compound to inhibit calcium receptor activity.
The screening method can be carried out in vivo or in vitro and is particularly useful to identify those Structure I xcex1,xcex1-disubstituted arylalkylamine derivatives most able to act as calcilytic compounds. In vivo assays include measuring a physiological parameter related to calcium receptor activity, such as serum hormone levels or serum calcium ion concentration. In vitro assays include measuring the ability of the calcilytic compound to affect intracellular calcium concentration, or cellular hormone secretion. Examples of hormones levels which can be affected by calcilytic compounds include PTH and calcitonin.
The calcilytic compounds described herein can be used as part of in vivo or in vitro methods. Preferably, the compounds are used in vivo to achieve a beneficial effect in a patient. Examples of in vitro uses, and other in vivo uses, include use in a method to identify other calcilytic compounds and use as a tool to investigate calcium receptor activity or the physiological effects of inhibiting calcium receptor activity in different organisms.
Other features and advantages of the invention will be apparent from the following detailed description of the invention, examples, and the claims.
The present application demonstrates the ability of calcilytic compounds to exert a physiologically relevant effect on a cell by illustrating the ability of such compounds to increase PTH secretion and also identifies a target site for calcilytic compounds. The present application is believed to be the first to demonstrate that calcilytic compounds can increase PTH secretion.
Calcium receptors are present on different cell types and can regulate different responses in different cell types. While the calcilytic compounds described herein are believed to act at a calcium receptor through a calcium receptor-activity modulating site, unless otherwise explicitly stated in the claims that a compound exerts an effect by acting at a calcium receptor through such a site, there is no intention to limit the claimed methods or compound to requiring inhibition of calcium receptor activity or any particular mode of action. Rather, the present application demonstrates that compounds able to inhibit calcium receptor activity, whose calcilytic activity can be measured in vivo or in vitro, exert significant physiological effects. For example, the present application demonstrates the ability of different calcilytic compounds to prevent Ca2+ inhibition of PTH and, thereby, result in an increase in PTH release.
Compounds binding at the calcium receptor-activity modulating site can be identified using a labeled compound binding to the site in a competition-binding assay format.
Preferred calcilytic compounds described herein are Structure I xcex1,xcex1-disubstituted arylalkylamine derivatives able to inhibit calcium receptor activity. Other aspects of the present invention include assays which can be used to identify those Structure I xcex1,xcex1-disubstituted arylalkylamine derivatives expected to be effective in inhibiting calcium receptor activity, and/or exerting a therapeutic effect in a patient; preferred groups of Structure I xcex1,xcex1-disubstituted arylalkylamine derivatives; and the use of the compounds described herein to treat different diseases or disorders.
Calcium receptors respond to changes in extracellular calcium levels. The exact changes resulting from calcium receptor activity depend on the particular receptor and the cell containing the receptor. For example, the in vitro effect of calcium on the calcium receptor in a parathyroid cell includes the following:
1. An increase in internal calcium [Ca2+]i. The increase is due to the influx of external calcium and/or to the mobilization of internal calcium. Characteristics of the increase in internal calcium include the following:
(a) A rapid (time to peak  less than 5 seconds) and transient increase in [Ca2+]i that is refractory to inhibition by 1 xcexcM La3+ or 1 xcexcM Gd3+ and is abolished by pretreatment with ionomycin (in the absence of extracellular Ca2+);
(b) The increase is not inhibited by di-hydropyridines;
(c) The transient increase is abolished by pretreatment for 10 minutes with 10 mM sodium fluoride;
(d) The transient increase is diminished by pretreatment with an activator of protein kinase C (PKC), such as phorbol myristate acetate (PMA), mezerein or (xe2x88x92)-indolactam V. The overall effect of the protein kinase C activator is to shift the concentration-response curve of calcium to the right without affecting the maximal response; and
(e) Pretreatment with pertussis toxin (100 ng/ml for  greater than 4 hours) does not affect the increase.
2. A rapid ( less than 30 seconds) increase in the formation of inositol-1,4,5-triphosphate and/or diacylglycerol. Pretreatment with pertussis toxin (100 ng/ml for  greater than 4 hours) does not affect this increase;
3. The inhibition of dopamine- and isoproterenol-stimulated cyclic AMP formation. This effect is blocked by pretreatment with pertussis toxin (100 ng/ml for  greater than 4 hours); and
4. The inhibition of PTH secretion. Pretreatment with pertussis toxin (100 ng/ml for  greater than 4 hours) does not affect the inhibition of PTH secretion.
Calcilytic activity of a compound can be determined using techniques such as those described in the examples below and those described in publications such as Nemeth et al., PCT/US92/07175, International Publication Number WO 93/04373, Nemeth et al., PCT/US93/01642, International Publication Number WO 94/18959, and Nemeth et al., PCT/US94/12117, International Publication Number WO 95/11211 (each of which are hereby incorporated by reference herein).
Calcilytic activity varies depending upon the cell type in which the activity is measured. For example, calcilytic compounds possess one or more, and preferably all, of the following characteristics when tested on parathyroid cells in vitro:
1. The compound blocks, either partially or completely, the ability of increased concentrations of extracellular Ca2+ to:
(a) increase [Ca2+]i,
(b) mobilize intracellular Ca2+,
(c) increase the formation of inositol-1,4,5-triphosphate,
(d) decrease dopamine- or isoproterenol-stimulated cyclic AMP formation, and
(e) inhibit PTH secretion;
2. The compound blocks increases in Clxe2x88x92 current in Xenopus oocytes injected with poly(A)+-mRNA from bovine or human parathyroid cells elicited by extracellular Ca2+, but not in Xenopus oocytes injected with water; and
3. Similarly, the compound blocks a response in Xenopus oocytes, injected with cloned nucleic acid expressing the calcium receptor, elicited by extracellular Ca2+ or a calcimimetic compound (i.e., a compound able to mimic the effect of extracellular Ca2+, including compounds potentiating the effect of extracellular Ca2+).
Calcium receptors are present in different cells. The pharmacological effects of the following cells, in response to extracellular Ca2+, is consistent with the presence of a calcium receptor: parathyroid cell, bone osteoclast, juxtaglomerular kidney cell, proximal tubule kidney cell, distal tubule kidney cell, central nervous system cell, peripheral nervous system cell, cell of the thick ascending limb of Henle""s loop and/or collecting duct, keratinocyte in the epidermis, parafollicular cell in the thyroid (C-cell), intestinal cell, trophoblast in the placenta, platelet, vascular smooth muscle cell, cardiac atrial cell, gastrin-secreting cell, glucagon-secreting cell, kidney mesangial cell, mammary cell, endocrine and exocrine cells in the pancreas, fat/adipose cell, immune cell, GI tract cell, skin cell, adrenal cell, pituitary cell, hypothalamic cell and cell of the subfornical organ.
The presence of a calcium receptor on the following cells have been confirmed using physical data, such as hybridization with nucleic acid encoding a calcium receptor: parathyroid cell, central nervous system cell, peripheral nervous system cell, cell of the thick ascending limb of Henle""s loop and/or collecting duct in the kidney, parafollicular cell in the thyroid (C-cell), intestinal cell, GI tract cell, pituitary cell, hypothalamic cell, cell of the subfornical organ, and endocrine and exocrine cells in the pancreas.
Structure I xcex1,xcex1-disubstituted arylalkylamine derivatives have the following chemical formula: 
where R1 is selected from the group consisting of: aryl, longer-length alk, and cycloalk. Preferably, R1 is either optionally substituted phenyl, optionally substituted pyridyl, optionally substituted benzothiopyranyl, optionally substituted carbazole, optionally substituted naphthyl, optionally substituted tetrahydronaphthyl, optionally substituted longer-length alkyl, optionally substituted longer-length alkenyl or optionally substituted cycloalk.
More preferably, R1 is either an optionally substituted phenyl; an optionally substituted naphthyl; an optionally substituted pyridyl; an optionally substituted benzothiopyranyl; an optionally substituted carbazole; unsubstituted longer-length alkyl; unsubstituted longer-length alkenyl; or monosubstituted longer-length alkyl or alkenyl, where the monosubstituent is either an optionally substituted phenyl or an optionally substituted cycloalkyl provided that the optionally substituted phenyl or optionally substituted cycloalkyl can have one to four substituents each independently selected from the group consisting of: alkoxy, lower-haloalkyl, S-unsubstituted alkyl, lower-haloalkoxy, unsubstituted alkyl, unsubstituted alkenyl, halogen, SH, CN, NO2, NH2 and OH;
R2 is selected from the group consisting of: lower alk, cycloalk, alkoxy, H, OH, xe2x95x90O, C(O)OH, C(O)O-lower alk, C(O)NH-lower alk, C(O)N(lower alk)2, SH, S-lower alk, NH2, NH-lower alk, and N(lower alk)2. More preferably, R2 is OH or alkoxy, even more preferably, R2 is OH or methoxy;
R3 and R4 is each independently lower alk or together cyclopropyl. Preferably, R3 and R4 are each independently a lower alkyl, more preferably, R3 and R4 are each independently methyl or ethyl;
R5 is aryl. Preferably, R5 is either optionally substituted naphthyl or optionally substituted phenyl. More preferably, R5 is substituted phenyl having a substituent in the meta or para position and optionally containing additional substituents;
R6 if present is either hydrogen, lower alkyl or lower alkenyl, wherein R6 is not present if R2 is xe2x95x90O. Preferably R6 is either hydrogen or lower alkyl, more preferably R6 is hydrogen.
Y1 is either covalent bond, alkylene, or alkenylene. Preferably, Y1 is either covalent bond or lower alkylene. More preferably, Y1 is methylene;
Y2 is alkylene. Preferably, Y2is lower alkylene. More preferably, Y2 is methylene;
Y3 is alkylene. Preferably, Y3 is lower alkylene. More preferably, Y3 is methylene;
Z is selected from the group consisting of: covalent bond, O, S, NH, N-lower alk, alkylene, alkenylene, and alkynylene, provided that if Z is either O, S, NH, or N-lower alk, then Y1 is not a covalent bond, further provided that Y1 and Z may together be a covalent bond. Preferably, Z is selected from the group consisting of: covalent bond, O, S, NH, N-lower alk, and alkylene. More preferably, Z is either O, S, lower alkylene, even more preferably, Z is O;
and pharmaceutically acceptable salts and complexes thereof.
xe2x80x9cAlkxe2x80x9d refers to either alkyl, alkenyl, or alkynyl. xe2x80x9cLower alkxe2x80x9d refers to either lower alkyl, lower alkenyl, or lower alkynyl, preferably, lower alkyl.
xe2x80x9cAlkenylxe2x80x9d refers to an optionally substituted hydrocarbon group containing at least one carbon-carbon double bond between the carbon atoms and containing 2-15 carbon atoms joined together. The alkenyl hydrocarbon group may be straight-chain or contain one or more branches. Branched- and straight-chain alkenyl preferably have 2 to 7 carbons, each of which may be optionally substituted. Alkenyl substituents are each independently selected from the group consisting of: lower alkyl, lower alkenyl, halogen, alkoxy, lower haloalkyl, lower haloalkoxy, methylene dioxy, unsubstituted aryl, unsubstituted cycloalkyl, OH, SH, CN, NO, NO2, NH2, CHxe2x95x90NNHC(O)NH2, CHxe2x95x90NNHC(S)NH2, CH2O-lower alkyl, C(O)lower alkyl, C(O)NH2, C(O)NH-lower alkyl, C(O)N(lower alkyl)2, C(O)OH, C(O)O-lower alkyl, NH-lower alkyl, N(lower alkyl)2, NHC(O)unsubstituted aryl, NHC(O)lower alkyl, Nxe2x95x90N-unsubstituted aryl, NHC(O)NH2, N(lower alkyl)C(O)lower alkyl, NHC(S)lower alkyl, N(lower alkyl)C(S)lower alkyl, NHS(O)lower alkyl, N(lower alkyl)S(O)lower alkyl, OC(O)lower alkyl, OCH2C(O)OH, OC(S)lower alkyl, S(O)lower alkyl, SC(O)lower alkyl, S-lower alkyl, S-lower haloalkyl, SO2-lower alkyl, SO2-lower haloalkyl, S(O)2NH2, S(O)2NH-lower alkyl, and S(O)2N(lower alkyl)2. Preferably, no more than three substituents are present. Even more preferably, the alkenyl is a lower alkenyl, which is an unsubstituted branched- or straight-chain alkenyl having 2 to 4 carbons.
xe2x80x9cAlkylxe2x80x9d refers to an optionally substituted hydrocarbon group joined by single carbon-carbon bonds and having 1-15 carbon atoms joined together. The alkyl hydrocarbon group may be straight-chain or contain one or more branches. Branched- and straight-chain alkyl preferably have 1 to 7 carbons, each of which may be optionally substituted. Alkyl substituents are each independently selected from the substituents described above for alkenyl. Preferably, no more than three substituents are present. More preferably, the alkyl is a lower alkyl, which is an unsubstituted branched- or straight-chain alkyl 1 to 4 carbons in length.
xe2x80x9cAlkynylxe2x80x9d refers to an optionally substituted hydrocarbon group containing at least one carbon-carbon triple bond between the carbon atoms and containing 2-15 carbon atoms joined together. The alkynyl hydrocarbon group may be straight-chain or contain one or more branches. Branched- and straight-chain alkynyl preferably have 2 to 7 carbons, each of which may be optionally substituted. Alkynyl substituents are each independently selected from the substituents described above for alkenyl. Preferably, no more than three substituents are present. More preferably, the alkynyl is a lower alkynyl, which is an unsubstituted branched- or straight-chain alkynyl having 2 to 4 carbons.
xe2x80x9cAlkenylenexe2x80x9d refers to an optionally substituted hydrocarbon chain containing at least one carbon-carbon double bond between the carbon atoms. The alkenylene chain has 2 to 6 carbons and is attached at two locations to other functional groups or structural moieties. The alkenylene substituents are each independently selected from the substituents described above for alkenyl. Preferably, no more than three substituents are present. More preferably, the alkenylene is a xe2x80x9clower alkenylene,xe2x80x9d which is an unsubstituted branched- or straight-chain alkenylene having 2 to 3 carbons.
xe2x80x9cAlkoxyxe2x80x9d refers to oxygen joined to an unsubstituted alkyl 1 to 12 carbon atoms in length, preferably 1 to 2 carbons in length. More preferably, the alkoxy is methoxy.
xe2x80x9cAlkylenexe2x80x9d refers to an optionally substituted hydrocarbon chain containing only carbon-carbon single bonds between the carbon atoms. The alkylene chain has 1 to 6 carbons and is attached at two locations to other functional groups or structural moieties. The alkylene substituents are each independently selected from the substituents described above for alkenyl. Preferably, no more than three substituents are present. More preferably, the alkylene is a xe2x80x9clower alkylene,xe2x80x9d which is an unsubstituted branched-, or straight-chain alkylene having 1 to 3 carbons.
xe2x80x9cAlkynylenexe2x80x9d refers to an optionally substituted hydrocarbon chain containing at least one carbon-carbon triple bond between the carbon atoms. The alkynylene chain has 2 to 6 carbons and is attached at two locations to other functional groups or structural moieties. The alkynylene substituents are each independently selected from the substituents described above for alkenyl. More preferably, the alkynylene is a xe2x80x9clower alkynylene,xe2x80x9d which is an unsubstituted branched- or straight-chain alkynylene having 2 to 3 carbons.
xe2x80x9cArylxe2x80x9d refers to an optionally substituted aromatic group with at least one ring having a conjugated pi-electron system, containing up to two conjugated or fused ring systems. Aryl includes carbocyclic aryl, heterocyclic aryl and biaryl groups, all of which may be optionally substituted. Preferably, the aryl is either optionally substituted phenyl, optionally substituted pyridyl, optionally substituted benzothiopyranyl, optionally substituted carbazole, optionally substituted naphthyl, optionally substituted tetrahydronaphthyl.
Different substituents are preferred for the Structure I left hand R1 aryl and the Structure I R5 right hand aryl. Preferably, the aryl has no more than five independently selected substituents.
Preferably, when R1 is an aryl, the aryl is either optionally substituted phenyl, optionally substituted pyridyl, optionally substituted benzothiopyranyl, optionally substituted carbazole, optionally substituted naphthyl, or optionally substituted tetrahydronaphthyl. Preferred, R1 substituents are each independently selected from the group consisting of: unsubstituted alkyl, unsubstituted alkenyl, halogen, alkoxy, lower haloalkyl, lower haloalkoxy, methylene dioxy, unsubstituted aryl, unsubstituted cycloalkyl, OH, SH, CN, NO, NO2, NH2, methylene dioxy, CHxe2x95x90NNHC(O)NH2, CHxe2x95x90NNHC(S)NH2, CH2O-unsubstituted alkyl, C(O)unsubstituted alkyl, C(O)NH2, C(O)NH-unsubstituted alkyl, C(O)N(unsubstituted alkyl)2, C(O)OH, C(O)O-unsubstituted alkyl, NH-unsubstituted alkyl, N(unsubstituted alkyl)2, NHC(O)unsubstituted aryl, NHC(O)unsubstituted alkyl, Nxe2x95x90N-unsubstituted aryl, NHC(O)NH2, N(unsubstituted alkyl)C(O)unsubstituted alkyl, NHC(S)unsubstituted alkyl, N(unsubstituted alkyl)C(S)unsubstituted alkyl, NHS(O)unsubstituted alkyl, N(unsubstituted alkyl)S(O)unsubstituted alkyl, NS(O)2 aryl, OC(O)unsubstituted alkyl, OCH2C(O)OH, OC(S)unsubstituted alkyl, S(O)unsubstituted alkyl, SC(O)unsubstituted alkyl, s-unsubstituted alkyl, S-unsubstituted haloalkyl, SO2-unsubstituted alkyl, SO2-unsubstituted haloalkyl, S(O)2NH2, S(O)2NH-unsubstituted alkyl, and S(O)2N(unsubstituted alkyl)2.
Preferred R1 aryl substituents are each independently selected from the group consisting of: alkoxy, methylene dioxy, N(CH3)2, C(O)OCH3, phenyl, lower-haloalkyl, S-unsubstituted alkyl, lower-haloalkoxy, unsubstituted alkyl, unsubstituted alkenyl, halogen, SH, CN, NO2, NH2, OH and sulfamoyl. More preferably, each R1 aryl substituent is independently selected from the group consisting of: unsubstituted C1-C7 alkyl, C1-C7 alkoxy, lower haloalkoxy, CF3, F, Cl, Br, CN, NO2 and sulfamoyl.
In another preferred embodiment, R1 is either 2-CN-phenyl, 2,3-dichloro phenyl, 2-nitro-phenyl, 2-cyano-3-chloro-phenyl, or 2,3-dichloro-4-sulfamoyl-phenyl.
R5 right hand aryl substituents are each independently selected from the substituents described above for alkenyl. In a preferred embodiment, the R5 aryl substituents are each independently selected from the group consisting of: methoxy, lower alkyl, lower haloalkoxy, CFH2, CHF2, CF3, OCH2CF3, F, Cl, Br, I, OH, SH, CN, NO2, NH2, methylene dioxy, NH-lower alkyl, N(lower alkyl)2, C(O)lower alkyl, S-lower alkyl, S(O)lower alkyl, S(O)2lower alkyl, OC(O)lower alkyl, SC(O)lower alkyl, OC(S)lower alkyl, NHC(O)lower alkyl, N(lower alkyl)C(O)lower alkyl, NHC(S)lower alkyl, N(lower alkyl)C(S)lower alkyl, NHS(O)lower alkyl, N(lower alkyl)S(O)lower alkyl, C(O)OH, C(O)O-lower alkyl, C(O)NH2, C(O)NH-lower alkyl, C(O)N(lower alkyl)2, S(O)2NH2, S(O)2NH-lower alkyl, and S(O)2N(lower alkyl) 2.
In another preferred embodiment, R5 aryl substituents are each independently selected from the group consisting of: methylene dioxy, methoxy, lower-haloalkyl, S-lower alkyl, lower-haloalkoxy, lower alkyl, halogen, SH, CN, OH, Cl, F, and Br. Preferred halogens are Cl, F, and Br.
xe2x80x9cCarbocyclic arylxe2x80x9d refers to an aromatic ring or ring system having all carbon atoms. The carbon atoms are optionally substituted.
xe2x80x9cCycloalkxe2x80x9d refers to an optionally substituted cyclic alkyl or an optionally substituted non-aromatic cyclic alkenyl and includes monocyclic and multiple ring structures such as bicyclic and tricyclic. The cycloalk has 3 to 15 carbon atoms, preferably, 5 to 12 carbon atoms. Optional substituents for the cycloalk are each independently selected from the group described above for alkenyl. Preferably, no more than three substituents are present. More preferably, the cycloalk is unsubstituted, even more preferably it is an unsubstituted cyclic alkyl. Preferred cycloalkyl groups include cyclohexyl and adamantyl.
xe2x80x9cHaloalkxe2x80x9d refers to substituted alkyl or substituted alkenyl, having no more than 4 carbons, where the substituents are halogens and at least one halogen is present. Preferably, the haloalk is an alkyl 1 to 3 carbons in length and the halogens are each independently either Cl or F, more preferably the alkyl has 2 carbons, more preferably the haloalkyl is a lower haloalkyl which has 1 carbon.
xe2x80x9cHeterocyclic arylxe2x80x9d refers to an aryl having 1 to 3 heteroatoms as ring atoms in the aromatic ring and the remainder of the ring atoms are carbon atoms. Suitable heteroatoms include oxygen, sulfur, and nitrogen. Examples of heterocyclic aryl include indolyl, pyridyl, quinolinyl, and isoquinolinyl.
xe2x80x9cLonger-length alkxe2x80x9d refers to either longer-length alkyl, longer-length alkenyl, or longer-length alkynyl; preferably, longer-length alkyl or longer-length alkenyl. More preferably a longer-length alk is 4 to 20 carbon atoms.
xe2x80x9cLonger-length alkenylxe2x80x9d refers to an optionally substituted hydrocarbon group containing at least one carbon-carbon double bond between the carbon atoms, and which contains 2-20 carbon atoms joined together. Preferably, the longer-length alkenyl is 4 to 20 carbon atoms. The longer-length alkenyl hydrocarbon group may be straight-chain or contain one or more branches. Longer-length alkenyl substituents are each independently selected from the alkenyl substituent list described above. Preferably, the longer-length alkenyl is either unsubstituted or has one cycloalk or phenyl substituent. More preferably, the cycloalk substituent, if present, is unsubstituted, and more preferably the cycloalk substituent, if present, is either cyclohexyl or adamantyl.
xe2x80x9cLonger-length alkylxe2x80x9d refers to an optionally substituted hydrocarbon group joined by single carbon-carbon bonds and which contains 1-20 carbon atoms joined together. Preferably, the longer-length alkyl is 4 to 20 carbon atoms. The longer-length alkyl hydrocarbon group may be straight-chain or contain one or more branches. Longer-length alkyl substituents are each independently selected from the alkenyl substituent list described above. Preferably, the longer-length alkyl is either unsubstituted or has one cycloalk or phenyl substituent. More preferably, the cycloalk substituent, if present, is unsubstituted, and more preferably the cycloalk substituent, if present, is either cyclohexyl or adamantyl.
xe2x80x9cLonger-length alkynylxe2x80x9d refers to an optionally substituted hydrocarbon group containing at least one carbon-carbon triple bond between the carbon atoms, and which contains 2-20 carbon atoms joined together. Preferably, the longer-length alkynyl is 4 to 20 carbon atoms. The longer-length alkynyl hydrocarbon group may be straight-chain or contain one or more branches. Longer-length alkynyl substituents are each independently selected from the alkenyl substituent list described above. Preferably, the longer-length alkynyl is either unsubstituted or has one cycloalk or phenyl substituent substituent. More preferably, the cycloalk substituent, if present, is unsubstituted, and more preferably the cycloalk substituent, if present, is either cyclohexyl or adamantyl.
xe2x80x9cHaloalkoxyxe2x80x9d refers to oxygen joined to a xe2x80x9chaloalk.xe2x80x9d Preferably, the haloalkoxy is a xe2x80x9clower-haloalkoxy,xe2x80x9d which is an oxygen joined to a lower-haloalkyl.
A. xcex1,xcex1-Disubstituted xcex2-Phenethylamine Derivatives
More preferred calcilytic compounds are Structure I derivatives where R1, R2, R3, R4, R6, Z, Y1, and Y2 are as described above for Structure I xcex1,xcex1-disubstituted arylalkylamine derivatives, including preferred groups (see, Section II, supra); and
R5 is either phenyl substituted with one to four independently selected substituents or an optionally substituted naphthyl having up to four independently selected substituents. R5 substituents are provided in Section II, supra., including preferred embodiments. More preferably R5 is either a substituted phenyl comprising a substituent in a meta or para position, more preferably, the substituent present in a meta or para position is either methyl, ethyl, isopropyl, methoxy, Cl, F, Br, or lower haloalkoxy.
The activity of different calcilytic compounds was measured using the Calcium Receptor Assay described below. Examples of compounds having an IC50xe2x89xa650 xcexcM include compounds 1, 9, 17, 25, 29, 42, 56, 79, 90, 101 and 164; examples of preferred compounds having an IC50xe2x89xa610 xcexcM include compounds 2, 3, 7, 8, 26, 27, 32, 33, 35, 37, 39, 41, 45, 48, 49, 59, 61, 66, 68, 71, 75, 93, 98, 103, 104, 110, 111, 114, 123, 124, 125, 128, 132, 144, 147, 152, 155, 158, 161, 162, 169 and 170; and examples of more preferred compounds having an IC50 less than  than 1 xcexcM include compounds 5, 6, 19, 20, 21, 28, 38, 40, 43, 44, 46, 47, 50, 51, 63, 64, 65, 67, 69, 72, 74, 96, 105, 106, 109, 112, 113, 115, 116, 117, 118, 119, 120, 121, 122, 126, 127, 129, 130, 131, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 145, 146, 148, 149, 150, 151, 153, 154, 156, 157, 159, 160, 163, 165, 166, 167, and 168.
B. Structure II Compounds Structure II compounds have the following structure: 
In one embodiment R1, R2, R3, and R4 are as described above for Structure I xcex1,xcex1-disubstituted arylalkylamine derivatives, including preferred groups (see, Section II, supra); and
R5 is either an optionally substituted naphthyl having one to four substituents independently selected from the group consisting of methyl, ethyl, isopropyl, methoxy, Cl, F, Br, or lower haloalkoxy, preferably the naphthyl is unsubstituted; or a substituted phenyl having one to four substituent with at least one substituent in a meta or para position selected from the group consisting of: lower alkyl, methoxy, Cl, F, Br, and lower haloalkoxy, more preferably a methoxy is present in the para or meta position; even more preferably, the remaining R5 substituents are independently selected from the group consisting of: methoxy, lower-haloalkyl, S-lower alkyl, lower-haloalkoxy, lower alkyl, halogen, SH, CN, OH, Cl, F, and Br.
provided that R1 is not 6-CN-2-pyridyl; and
further provided that if R5 is 3,4 dimethoxy-phenyl, then R1 is not CH3(CH2)5O-phenyl; 2-cyclopentyl-phenyl; 2-Cl-phenyl; 2-CN-phenyl; 2-(3-furanyl)phenyl; or 4-(1,2,-benzisothiazol); preferably, R5is not 3,4 dimethoxy phenyl;
further provided that if R5 is 4-methoxy-phenyl, then R1 is not 2-cyclopentyl-phenyl; 2-CH3-phenyl; 2-benzyl-phenyl; 3-CH3, 4-CH3SO2-phenyl; or 4-(1,2,-benzisothiazol);
further provided that if R5 is 4-Cl-phenyl, then R1 is not 2-CH3-phenyl , 5-iso-propyl-phenyl; 2-CH3-phenyl; 4-CH3-phenyl; phenyl; 2-Cl-phenyl; 4-Cl-phenyl; 2-methoxy, 4-CH3CHCH-phenyl; 3,4 CH3-phenyl; 2,4 CH3-phenyl; 2,3 CH3-phenyl; 2-iso-propyl, 5-CH3-phenyl; pyridyl; or 1-imidazole; 4-(1,2,-benzisothiazol); preferably, R4 is either not 4-Cl, or R4 is 3,4 dichlorophenyl; and
further provided that if R5 is 3,5, dimethyl, 4-methoxy-phenyl, then R1 is not 4-CH3, 6-CN-2-pyridyl; or thiophenecarboxamide; preferably, R5 is not 3,5, dimethyl, 4-methoxy-phenyl.
In another embodiment, R2, R3, and R4 are as described above for Structure I xcex1,xcex1-disubstituted arylalkylamine derivatives, including preferred groups (see, Section II, supra);
R5 is either an optionally substituted naphthyl having one to four substituents independently selected from the group consisting of methyl, ethyl, isopropyl, methoxy, Cl, F, Br, and lower haloalkoxy, preferably the naphthyl is unsubstituted; or a substituted phenyl having one to four substituent with at least one substituent in a meta or para position selected from the group consisting of: methyl, ethyl, isopropyl, methoxy, Cl, F, Br, and lower haloalkoxy, more preferably a methoxy is present in the para or meta position; even more preferably, the remaining R5 substituents are independently selected from the group consisting of: methoxy, lower-haloalkyl, S-lower alkyl, lower-haloalkoxy, lower alkyl, halogen, SH, CN, OH, Cl, F, and Br; and
R1 is either 2-CN-phenyl, 2,3-dichloro phenyl, 2-nitro-phenyl, 2-cyano-3-chloro-phenyl, 2,3-dichloro-4-sulfamoyl-phenyl, an optionally substituted pyridyl, an optionally substituted benzothiopyranyl, or an optionally substituted carbazole, where the optionally present substituents for the pyridyl, benzothiopyranyl, and carbazole as described in Section II supra, for aryl R1 substituents, including preferred substituents, and are even more preferably independently selected from the group consisting of: methoxy, lower-haloalkyl, S-lower alkyl, lower-haloalkoxy, lower alkyl, halogen, SH, CN, OH, Cl, F, Br and sulfamoyl.
C. R2-group Stereochemistry
The different calcilytic compounds described herein can have different stereochemistry around different groups. In an embodiment of the present invention the Structure I compounds have the following absolute configuration structure with respect to R2: 
The calcilytic compounds described herein can be formulated as a pharmaceutical composition to facilitate the administration of the compound to a patient. Preferred formulations contain a pharmaceutically acceptable carrier and a calcilytic compound as described in Section II, supra., including the different embodiments.
Examples of suitable carriers are provided below, in Section V, xe2x80x9cAdministration,xe2x80x9d and include calcium carbonate, calcium phosphate, lactose, glucose, sucrose, gelatin, vegetable oils, polyethylene glycols and physiologically compatible solvents.
Compounds inhibiting calcium receptor activity can be used to confer beneficial effects to patients suffering from a variety of diseases or disorders. Diseases or disorders which can be treated using a calcilytic compound are known in the art and can be identified using the present application as a guide. For example, diseases or disorders can be identified based on the functional responses of cells regulated by calcium receptor activity.
Diseases and disorders which can be treated using the calcilytic compounds described herein include those due to different cellular defects related to calcium receptor activity in different cells, such as a defective calcium receptor or an abnormal number of calcium receptors, a defective intracellular protein acted on by a calcium receptor, or a defective protein or an abnormal number of proteins acting on a calcium receptor.
Functional responses of cells regulated by the calcium receptor are known in the art, including PTH secretion by parathyroid cells, calcitonin secretion by C-cells, bone resorption by osteoclasts, and Ca2+ secretion by kidney cells. Such functional responses are associated with different diseases or disorders.
For example, isolated osteoclasts respond to increases in the concentration of extracellular Ca2+ with corresponding increases in [Ca2+]i arising partly from the mobilization of intracellular Ca2+. Increases in [Ca2+]i in osteoclasts are associated with the inhibition of bone resorption.
Renin secretion from juxtaglomerular cells in the kidney is depressed by increased concentrations of extracellular Ca2+. Extracellular Ca2+ causes the mobilization of intracellular Ca2+ in these cells. Other kidney cells respond to extracellular Ca2+ as follows: elevated Ca2+ inhibits formation of 1,25(OH)2-vitamin D by proximal tubule cells, stimulates production of calcium-binding protein in distal tubule cells, and inhibits tubular reabsorption of Ca2+ and Mg2+ in the thick ascending limb of Henle""s loop (MTAL), and reduces vasopressin action in the cortical collecting duct.
Other examples of functional responses affected by extracellular Ca2+ include promoting differentiation of intestinal goblet cells, mammary cells, and skin cells; inhibiting atrial natriuretic peptide secretion from cardiac atria; reducing cAMP accumulation in platelets; altering gastrin and glucagon secretion; acting on perivascular nerves to modify cell secretion of vasoactive factors; and affecting cells of the central nervous and peripheral nervous systems.
Diseases and disorders which might be treated or prevented, based upon the affected cells, include bone and mineral-related diseases or disorders; hypoparathyroidism; those of the central nervous system such as seizures, stroke, head trauma, spinal cord injury, hypoxia-induced nerve cell damage, such as occurs in cardiac arrest or neonatal distress, epilepsy, neurodegenerative diseases such as Alzheimer""s disease, Huntington""s disease and Parkinson""s disease, dementia, muscle tension, depression, anxiety, panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder, schizophrenia, neuroleptic malignant syndrome, and Tourette""s syndrome; diseases involving excess water reabsorption by the kidney, such as syndrome of inappropriate ADH secretion (SIADH), cirrhosis, congestive heart failure, and nephrosis; hypertension; preventing and/or decreasing renal toxicity from cationic antibiotics (e.g., aminoglycoside antibiotics); gut motility disorders such as diarrhea and spastic colon; GI ulcer diseases; GI diseases with excessive calcium absorption such as sarcoidosis; autoimmune diseases and organ transplant rejection; squamous cell carcinoma; and pancreatitis.
While calcilytic compounds of the present invention will typically be used to treat human patients, they may also be used to treat similar or identical diseases or disorders in other warm-blooded animal species, such as other primates, farm animals such as swine, cattle, and poultry; and sports animals and pets such as horses, dogs and cats.
Preferably, calcilytic compounds are used in the treatment of bone and mineral-related diseases or disorders. Bone and mineral-related diseases or disorders comprise a diverse class of disorders affecting nearly every major organ system in the body. Examples of bone and mineral-related diseases or disorders include osteosarcoma, periodontal disease, fracture healing, osteoarthritis, rheumatoid arthritis, Paget""s disease, humoral hypercalcemia malignancy, and osteoporosis. More preferably, calcilytic compounds are used to treat osteoporosis, a disease characterized by reduced bone density and an increased susceptibility to fractures. Osteoporosis is associated with aging, especially in women.
One way of treating osteoporosis is by altering PTH secretion. PTH can have a catabolic or an anabolic effect on bone. Whether PTH causes a catabolic effect or an anabolic effect seems to depend on how plasma levels of PTH are altered. When plasma levels of PTH are chronically elevated, as in hyperparathyroid states, there is a net loss of bone. In contrast, intermittent increases in plasma PTH levels, as achieved by administration of exogenous hormone, result in new bone formation. Anabolic action of PTH on bone is described, for example, by Dempster et al., Endocrin. Rev. 14:690-709, 1993.
As demonstrated by the Examples provided below, calcilytic compounds stimulate secretion of PTH. Such calcilytic compounds can be used to increase bone formation in a patient, for example, by intermittent dosing, thus achieving intermittent increases in the circulating levels of PTH.
The calcilytic compounds described by the present invention can be formulated for a variety of modes of administration, including systemic and topical or localized administration. Techniques and formulations generally may be found in Remington""s Pharmaceutical Sciences, 18th ed., Mack Publishing Co., Easton, Pa., 1990 (hereby incorporated by reference herein).
Suitable dosage forms, in part, depend upon the use or the route of entry, for example, oral, transdermal, transmucosal, or by injection (parenteral). Such dosage forms should allow the compound to reach a target cell whether the target cell is present in a multicellular host or in culture. For example, pharmacological compounds or compositions injected into the blood stream should be soluble. Other factors are known in the art, and include considerations such as toxicity and dosage forms which retard the compound or composition from exerting its effect.
Compounds can also be formulated as pharmaceutically acceptable salts and complexes thereof. Pharmaceutically acceptable salts are non-toxic salts in the amounts and concentrations at which they are administered. The preparation of such salts can facilitate the pharmacological use by altering the physical characteristics of the compound without preventing it from exerting its physiological effect. Useful alterations in physical properties include lowering the melting point to facilitate transmucosal administration and increasing the solubility to facilitate administering higher concentrations of the drug.
The pharmaceutically acceptable salt of the different compounds may be present as a complex. Examples of complexes include an 8-chlorotheophylline complex (analogous to, e.g., dimenhydrinate:diphenhydramine 8-chlorotheophylline (1:1) complex; Dramamine) and various cyclodextrin inclusion complexes.
Pharmaceutically acceptable salts include acid addition salts such as those containing sulfate, hydrochloride, fumarate, maleate, phosphate, sulfamate, acetate, citrate, lactate, tartrate, methanesulfonate, ethanesulfonate, benzenesulfonate, p-toluenesulfonate, cyclohexylsulfamate and quinate. Pharmaceutically acceptable salts can be obtained from acids such as hydrochloric acid, maleic acid, sulfuric acid, phosphoric acid, sulfamic acid, acetic acid, citric acid, lactic acid, tartaric acid, malonic acid, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, cyclohexylsulfamic acid, fumaric acid, and quinic acid.
Pharmaceutically acceptable salts also include basic addition salts such as those containing benzathine, chloroprocaine, choline, diethanolamine, ethylenediamine, meglumine, procaine, aluminum, calcium, lithium, magnesium, potassium, sodium, ammonium, alkylamine, and zinc, when acidic functional groups, such as carboxylic acid or phenol are present. For example, see Remington""s Pharmaceutical Sciences, 18th ed., Mack Publishing Co., Easton, Pa., p. 1445, 1990. Such salts can be prepared using the appropriate corresponding bases.
Pharmaceutically acceptable salts can be prepared by standard techniques. For example, the free-base form of a compound is dissolved in a suitable solvent, such as an aqueous or aqueous-alcohol in solution containing the appropriate acid and then isolated by evaporating the solution. In another example, a salt is prepared by reacting the free base and acid in an organic solvent. (See, e.q., PCT/US92/03736, hereby incorporated by reference herein.)
Carriers or excipients can also be used to facilitate administration of the compound. Examples of carriers include calcium carbonate, calcium phosphate, various sugars such as lactose, glucose, or sucrose, or types of starch, cellulose derivatives, gelatin, vegetable oils, polyethylene glycols and physiologically compatible solvents. Examples of physiologically compatible solvents include sterile solutions of water for injection (WFI), saline solution and dextrose.
The calcilytic compounds can be administered by different routes including intravenous, intraperitoneal, subcutaneous, intramuscular, oral, topical (transdermal), or transmucosal administration. For systemic administration, oral administration is preferred. For oral administration, for example, the compounds can be formulated into conventional oral dosage forms such as capsules, tablets, and liquid preparations such as syrups, elixirs, and concentrated drops.
Alternatively, injection (parenteral administration) may be used, e.g., intramuscular, intravenous, intraperitoneal, and subcutaneous. For injection, the compounds of the invention are formulated in liquid solutions, preferably, in physiologically compatible buffers or solutions, such as saline solution, Hank""s solution, or Ringer""s solution. In addition, the compounds may be formulated in solid form and redissolved or suspended immediately prior to use. Lyophilized forms can also be produced.
Systemic administration can also be by transmucosal or transdermal means. For transmucosal or transdermal administration, penetrants appropriate to the barrier to be permeated are used in the formulation. Such penetrants are generally known in the art, and include, for example, for transmucosal administration, bile salts and fusidic acid derivatives. In addition, detergents may be used to facilitate permeation. Transmucosal administration, for example, may be through nasal sprays, rectal suppositories, or vaginal suppositories.
For topical administration, the compounds of the invention can be formulated into ointments, salves, gels, or creams, as is generally known in the art.
The amounts of various calcilytic compounds to be administered can be determined by standard procedures taking into account factors such as the compound IC50, EC50, the biological half-life of the compound, the age, size and weight of the patient, and the disease or disorder associated with the patient. The importance of these and other factors to be considered are known to those of ordinary skill in the art. Generally, it is an amount between about 0.1 and 50 mg/kg, preferably 0.01 and 20 mg/kg of the animal to be treated.